Книги по МРТ КТ на английском языке / Neurosurgery Fundamentals Agarval 1 ed 2019

[86]de Gans K, de Haan RJ, Majoie CB, et al; PATCH Investigators. PATCH: platelet transfusion in cerebral haemorrhage: study protocol for a multicentre, randomised, controlled trial. BMC Neurol. 2010; 10:19

[87]Fredriksson K, Norrving B, Strömblad LG. Emergency reversal of anticoagulation after intracerebral hemorrhage. Stroke. 1992; 23(7):972–977

[88]Eerenberg ES, Kamphuisen PW, Sijpkens MK, Meijers JC, Buller HR, Levi M. Reversal of rivaroxaban and dabigatran by prothrombin complex concentrate: a randomized, placebo-controlled, crossover study in healthy subjects. Circulation. 2011; 124(14):1573–1579

[89]Glund S, Stangier J, Schmohl M, et al. Safety, tolera- bility, and efficacy of idarucizumab for the reversal of the anticoagulant effect of dabigatran in healthy male volunteers: a randomised, placebo-con- trolled, double-blind phase 1 trial. Lancet. 2015; 386(9994):680–690

[90]Macpherson BC, MacPherson P, Jennett B. CT evidence of intracranial contusion and haematoma in relation to the presence, site and type of skull fracture. Clin Radiol. 1990; 42(5):321–326

[91]Miller JD, Jennett WB. Complications of depressed skull fracture. Lancet. 1968; 2(7576):991–995

[92]Başkaya MK. Inadvertent intracranial placement of a nasogastric tube in patients with head injuries. Surg Neurol. 1999; 52(4):426–427

[93]Seebacher J, Nozik D, Mathieu A. Inadvertent intracranial introduction of a nasogastric tube, a complication of severe maxillofacial trauma. Anesthesiology. 1975; 42(1):100–102

[94]Ignelzi RJ, VanderArk GD. Analysis of the treatment of basilar skull fractures with and without antibiotics. J Neurosurg. 1975; 43(6):721–726

[95]Lende RA, Erickson TC. Growing skull fractures of childhood. J Neurosurg. 1961; 18:479–489

[96]Kaufman HH. Civilian gunshot wounds to the head. Neurosurgery. 1993; 32(6):962–964, discussion 964

[97]Benzel EC, Day WT, Kesterson L, et al. Civilian craniocerebral gunshot wounds. Neurosurgery. 1991; 29(1):67–71, discussion 71–72

9  Spinal Trauma

Katherine E Wagner, Jamie Ullman

9.1  Introduction

Traumatic injuries to the spinal column and cord can be seen following motor vehicle crashes, violence, sports, and even falls. These patients should be evaluated promptly by the trauma team and spine surgeon. The basic tenets of resuscitation apply; airway, breathing, and circulation should be evaluated first, as part of the standard primary survey. An evaluation of rectal tone is an essential part of the assessment of neurological function in patients with potential spinal trauma. Furthermore, patients may have concomitant head trauma, long bone fractures, and internal injuries. During the initial postinjury period, patients are generally kept in a hard cervical collar until it is “cleared,” clinically and/or radiographically.

9.2  Examination

The American Spinal Injury Association (ASIA) scale, outlined in Table 9.1, is a useful tool in the acute setting, and is ideally performed within 72 hours of the injury. Sometimes, patients with devastating injuries show signs of improvement after 24–72 hours, so the most meaningful score is obtained later.1

9.3  Imaging

The decision to image a patient’s spine depends on their level of wakefulness and ability to participate in a neurological examination.

Awake patients with no neurological symptoms or neck pain, no distracting injuries with a full, painless range of motion at the neck do not require immobilization or imaging.

150

Table 9.1  American Spinal Injury Association grading system

Grade Description

AComplete injury: No sensory or motor function preserved below the injury, including the sacral elements S4-S5

BIncomplete injury: Sensory, but not motor, function preserved below the neurological level

CIncomplete injury: Motor function is preserved below the neurological level. More than half of the key

muscles below the level have < 3 out of 5 strength

DIncomplete: Motor function is preserved below the neurological level

More than half of the key muscles below the level have

≥ 3 out of 5 strength

ENormal motor and sensory function

These guidelines stem from the National Emergency X-Radiography Utilization Study (NEXUS) results.2 Criteria for imaging a patient with suspected blunt vascular injury are described later.

Awake patients with neurological symptoms should remain in a collar and get a cervical CT scan. If the CT is negative but the patient continues to have symptoms, including pain or numbness, an MRI with short inversion time inversion recovery (STIR) sequences should be obtained within 48 hours to evaluate the disc spaces, cord, and ligaments. If that is unremarkable, flexion/extension X-rays are next. If no injury or instability is

found, the collar can be used for comfort. Patients who cannot safely enter the MRI machine (i.e., they have incompatible hardware) can be evaluated with flexion/ extension films.2

Obtunded patients should have a CT scan of the neuroaxis as part of their trauma workup and pan-scan.

One school of thought suggests obtaining an MRI of the cervical spine within 48 hours if there is a need to remove the collar. However, others have suggested that clearance based on careful review of CT scan alone is sufficient in an obtunded trauma patient.

9.4  Shock

Patients can present in hemorrhagic shock from other injuries, or in frank spinal shock with spinal cord injury (SCI) above T1.

Avoiding hypoxia and hypotension is crucial in minimizing secondary injury to the spinal cord.

Elevating the mean arterial pressure to 85–90 mmHg with monitoring in an intensive care unit can result in better outcomes.3 Of note, return of the bulbocavernosus reflex indicates complete SCI as opposed to just spinal shock.

9.5 Steroids

There is no Class I evidence supporting the use of steroids like methylprednisolone in patients with SCI. Animal models with very early administration of steroids suggest a potential benefit. However, the National Acute Spinal Cord Injury Studies (NASCIS)

I, II, and III do not demonstrate convincingly sustained improvements in patient outcomes after administration.4,​5 There is strong evidence linking steroids to gastrointestinal hemorrhages4 and wound infections.5

9.6  Immobilization

Cervical collars may be hard (e.g., Aspen or Miami J) or soft.

•Soft collars do not limit motion but can be useful after surgery for comfort.

•The compressed foam Philadelphia collar may be utilized by emergency medical techicians. to limit motion in the cervical spine.

The sterno-occipital-mandibular immobilization device (SOMI brace) has an anterior piece, rigid shoulder supports, and removable mandibular support.

•The SOMI can help limit motion at the craniocervical junction, help maintain alignment, and minimize motion in the lower cervical spine and cervicothoracic junction.6

•The Minerva brace, a cervicothoracic orthosis, is a similar device in the market.

The halo vest offers another form for rigid fixation of the occipital cervical junction ( Fig. 9.1).6,​7

•The pins need to torque to 8 lb at 24 and 48 hours after placement.

•Excessive tightening can penetrate or fracture the skull.7

“Snaking” or excessive motion of the lower cervical spine is a potential issue with the halo vest.

Thoracolumbosacral and lumbosacral orthoses (TLSO/LSO) minimize movement of the torso.

151

Right

C3

Fig. 9.1  Placement of the Halo. (Reproduced from Ullman J, Raksin P, Atlas of Emergency Neurosurgery, 1st edition, ©2015, Thieme Publishers, New York.)

Left

9.7  Spinal Cord Syndromes

These result from incomplete injuries to the cord.

temperature below the level of the lesion, and preserved posterior column function.

•Outcomes: Poor prognosis; most patients have no or minimal improvement in their deficits.8

9.7.1  Anterior Cord

Syndrome

•Mechanism: Cord infarction in areas supplied by the anterior spinal artery ( Fig. 9.2).

•Deficit: Sudden-onset paraplegia or quadriplegia; loss of pain and

152

9.7.2  Central Cord Syndrome

It is the most common spinal cord syndrome ( Fig. 9.3).9

•Mechanism: Neck extension

◦Usually occurs in patients with bony spurs, thickened ligaments, or herniated discs who suffer

C4-t4

Fig. 9.3  Central cord syndrome. (Reproduced from Alberstone C, Benzel E, Najm I et al, Anatomic Basis of Neurologic Diagnosis, 1st edition, ©2009, Thieme Publishers, New York.)

hyperextension from a fall or motor vehicle accident (MVA).

•Bimodal distribution: Younger patients with congenital stenosis and severe traumas and older patients with degenerative stenosis and even minor traumas.9,​10

•The long tract fibers in the center of the cord may swell and, since they are located in a watershed vascular territory, may suffer temporary ischemia.

•Deficit: Greater motor deficits in the upper extremities than the lower, distal more than proximal. Sensory findings may vary, and some patients become frankly myelopathic.

•Outcomes: Prognosis is guarded. Lower extremity and bowel/bladder function can recover, while upper extremity function is variable.9,​10

•There is controversy about the timing of treatment.9

◦Some advocate laminectomy and possible fusion on the same admission, while others will do the case electively after the patient has some physical therapy/rehabilitation.

◦If the patient deteriorates, urgent surgery is warranted.

◦Steroid use is also controversial.

9.7.3  Posterior Cord

Syndrome

•Mechanism: Can result from injury to the posterior spinal artery.

•Deficit: Results in pain and paresthesias.

•Relatively rare.

9.7.4  Brown-Séquard

Syndrome ( Fig. 9.4)

•Mechanism: Cord hemisection, often traumatic.11

•Deficit: Ipsilateral motor paralysis; loss of proprioception, vibration sense with contralateral loss of pain and temperature.

•Outcomes: Variable prognosis.

9.8  Spinal Column Model

White and Panjabi put forward the concept of spinal stability as the ability of the spine to limit movements under normal, physiological conditions to prevent injury to or irritation of the spinal cord and nerve roots and prevent deformity and mechanical pain. Francis Denis proposed the widely used three-column model for evaluating spine

153

Right

T4

Ipsilateral loss of

position and vibration sense Ipsilateral hemiparesis

Left

Fig. 9.4  Brown-Séquard syndrome. (Reproduced from Alberstone C, Benzel E, Najm I et al, Anatomic Basis of Neurologic Diagnosis, 1st edition, ©2009, Thieme Publishers, New York.)

trauma ( Fig. 9.5).12,​13,​14,​15 His model was designed for the thoracic and lumbar spine, but can be applied to the lower cervical spine as well. Fractures involving one column are generally stable; fractures involving two or three columns are considered unstable and may require surgery.12,​13,​14,​15 Denis also

154

Fig. 9.5  The Denis classification spinal columns—ante- rior, middle, and posterior, and major spinal fractures. (Reproduced from Jallo J, Vaccaro A, Neurotrauma and Critical Care of the Spine, 1st edition, ©2008, Thieme Publishers,

New York.)

outlined five types of fractures seen in the thoracolumbar region (refer to thoracolumbar injury section).

•The anterior column: Anterior longitudinal ligament (ALL), anterior two-thirds of the vertebral body and disc, including the annulus fibrosus.

•The middle column: Remaining posterior third of the vertebral body and disc, including the annulus fibrosus, posterior longitudinal ligament (PLL).

•The posterior column: Structures posterior to the PLL; pedicle, facet joints, ligamentum flavum, interspinous ligaments.

The rest of this chapter outlines various spinal injuries and their management.

9.9  Cervical Spine

Paramedics generally perform spinal immobilization and place a cervical collar on patients who may have a spinal column injury. Up to 25% of SCIs occur after the trauma, secondary to the way the patient is handled and transported.3 Spinal immobilization is contraindicated in penetrating trauma (i.e., gunshots, stabbings), as it has increased morbidity and mortality with higher risk of increased intracranial pressure, pressure sores, and aspiration.3

Injuries at or above C3 can produce bulbar-cervical dissociation.

These patients die unless cardiopulmonary resuscitation is started shortly after injury. Survivors are quadriplegic and ventilator dependent.

9.10  Cervical Injuries

9.10.1  Blunt Cerebrovascular

Injuries

•Blunt-force trauma to the head, face, or neck or high-speed deceleration to the thorax can cause blunt cerebrovascular injuries (BCVI).

•Injuries to the carotid and/or vertebral arteries may present as devastating

strokes. There is still controversy about which patients should be screened.

The Denver criteria (below) can be used to determine which patients should undergo CT angiogram of the head and neck.

•The criteria are divided into signs and symptoms of a BCVI and risk factors. Patients with any of these should be considered for CTA.

•Treatment is generally anticoagulation or antiplatelet therapy.16,​17

◦Signs and symptoms: Focal neurolog- ical deficit, especially with an exam- ination inconsistent with patient’s CT head; stroke on CT head; arterial hemorrhage, expanding hematoma; cervical bruit.

◦Risk factors: Le Forte II or III fractures; basilar skull fractures involving carotid canal; cervical spine fractures, especially those involving transverse foramen; diffuse axonal injury with Glasgow

Coma Scale less than 6 or anoxic brain injury with hanging or near hanging mechanism.

9.10.2  Atlanto-occipital

Dislocation

•Generally seen in high-energy traumas, more common in children.18

•Presentation can vary from minimal neurological findings to bulbar-cervical dislocation causing respiratory arrest and death.18

•Type I injuries: The occiput is displaced anteriorly to atlas.

•Type II injuries: The occiput is distracted away from the atlas.

•Type III injuries: The occiput is displaced posteriorly to atlas.

155

•Radiographic Measurement: Distraction via a cervical collar or traction is contraindicated.18

◦Powers ratio is defined as the distance from the tip of the basion to the posterior arch of C1 divided by the distance from the opisthion to the anterior arch of C1. Normal is a ratio < 1.

◦Basion-Dens Interval (BDI): normal < 12 mm on plain radiographs.

•A halo orthosis may be used to immobilize the neck, especially before definitive surgery; some authors state all patients require a posterior occipital-cervical fusion.18

•Patients with incomplete injuries may improve with stabilization.

9.10.3  Occipital Condyle

Fractures

•Patients have head trauma and skull fractures ( Fig. 9.6).

Look for condyle fractures in trauma patients with lower cranial nerve palsies (usually cranial nerve [CN] XII; CN VI, IX, and X can also be affected).

•Persistent neck pain, or reduced mobility in the upper cervical spine.

•Displaced bone fragments may compress the brainstem.

•Evaluate for rotatory subluxation and concomitant traumatic brain injury.19,​20

•There are two major classification schemes for these fractures ( Table 9.2).

9.10.4  Atlanto-axial

Dislocation

•Refers to loss of stability between atlas and axis (C1 and C2).

•Increased atlanto-dens interval.

156

Fig. 9.6  CT scan with fracture of the occipital condyle and basilar skull. (Reproduced from Jallo J, Vaccaro A, Neurotrauma and Critical Care of the Spine, 1st edition, ©2008, Thieme Publishers, New York.)

◦Normal in Adults < 2–3 mm, Children < 5 mm

•Can be traumatic or secondary to certain diseases. Fig. 9.7 shows an injury causing atlanto-axial dislocation. The transverse ligament is now just attached to a bone fragment as the result of a comminuted C1 fracture. The C1 lateral mass is displaced and the spine is unstable.

◦Associated conditions include Down Syndrome, Morquio Syndrome, and rheumatoid arthritis.21

◦A purely traumatic atlanto-axial dislocation in the absence of another predisposing risk factor is rare— evaluate patients with the above conditions carefully, and rule out these conditions in patients with unexplained deficits localizing to the high cervical cord.21

◦Treatments include cervical traction and posterior fusion with or without a transoral odontoidectomy.

9.11  C1 Fractures

•Isolated C1 fractures do not usually result in deficits unless they are not properly managed ( Fig. 9.8 and Fig. 9.9).19

•Evaluate the integrity of the transverse ligament.

•A Jefferson fracture is a C1 burst fracture, classically with fractures in both anterior and both posterior arches ( Fig. 9.8).19

◦Associated with diving head first into shallow water (i.e., axial loading onto the head).

◦If the transverse ligament is intact, the cervical spine should be immobilized for 10–12 weeks ( Fig. 9.9). If it is NOT intact, a C1–C2 fusion or halo fixation for 12 weeks is advised.

•The Rule of Spence can help determine the stability of the transverse ligament. The left and right C1 lateral masses

generally do not overhang C2. If the sum of the overhang of the left and right C1 lateral masses is greater than 7 mm, the transverse ligament may be injured, and should be evaluated with a treatment algorithm for isolated atlas fractures is shown in Fig. 9.10.19

9.11.1  Odontoid (Dens)

Fractures

•Most common C2 (axis) fractures; make up 7–14% of traumatic cervical spine injuries.

•Often present with high cervical pain; mechanism of injury can vary.19,​20

•Type I fractures involve the tip of the dens ( Fig. 9.11).

158

Fig. 9.8  Common C1 fractures. (a) Lateral mass fracture. (b) Posterior arch fracture. (c) Classic Jefferson fracture. (Reproduced from Jallo J, Vaccaro A, Neurotrauma and Critical Care of the Spine, 1st edition, ©2008, Thieme Publishers, New York.)

Fig. 9.9  Comminuted C1 lateral mass fracture and associated atlanto-axial instability. The attachment of the transverse ligament to the spinal column has been injured. (Reproduced from Bambakidis N, Dickman C, Spetzler R et al, Surgery of the Craniovertebral Junction, 2nd edition, ©2012, Thieme Publishers, New York.)

◦They are generally stable and treated with a collar, unless atlanto-occipital dislocation is present. Then options include surgery or immobilization with a halo or collar.

Type II fractures occur where the odontoid meets the vertebral body. These are the most common odontoid fractures and have a high rate of nonunion. These are generally unstable and treated with surgery or immobilization. If comminuted fragments are present, the fracture is unstable and surgery should be considered.